Around here, a single engine 4-place will run you around $100/hr wet (includes fuel). Hours are usually measured on the Hobbs which is on from engine startup to shutdown. Some places charge on tach time but that's usually the exception to the rule. Keep in mind that you're not going to be able to simply jump in the plane and go. You need to take into account preptime, the walk-around/preflight, clearance delays, etc... This can add up to anywhere between a half-hour to an hour or longer depending on how anal your pilot is, how congested the field is, the type of field, the type of flight, the type of aircraft, the weather, etc...